Mozilla has already done a lot to clean up the user interface of its successful web browser, but it would seem they're not yet done. As someone who finds the current interface a little... Chaotic and distracting, I'm quite happy with the changes they're currently proposing. They basically pointed at Chrome and said "pretty much that".

I find it more interesting to look at Fennec - their mobile version.
Sure it's not as news sensationalistic, but on the mobile, tiny screen platform UI matters A LOT MORE.

And Firefox is very different from the others, on mobile. They also asked feedback several times there and didnt get much, because, once again, it wasn't sensationalistic. Hard to bash Firefox mobile on UI design (easy to bash it on performances)